This section is from the book "The National Capitol. Its Architecture Art And History", by George C. Hazelton, Jr. Also available from Amazon: The National Capitol Its Architecture Art and History.
The House post-office and restaurant are upon this floor, east of the main corridor of the Capitol. The bath-rooms of the House also were formerly here, but have since been moved to the sub-basement near the furnace and engine rooms. Their space was incorporated into the restaurant. They are for the use of Representatives and certain employes of the building. Some of the tubs are made of solid blocks of marble, chiseled at the time of the erection of the extensions, but the majority are porcelain-lined. The two attendants, unlike those of the Senate who are exclusively for the comfort of Senators, wait upon both the Representatives and employes.